Correlations between leaf dry mass per unit area (LMA) and light-saturated photosynthetic rate (A
) or maximum rates of carboxylation (V
); and between A
and leaf nitrogen content per unit area (N
) or leaf nitrogen content per unit mass (N
) in three Rhododendron species. “●”, “▲” and “■” stand for R. yunnanense, R. irroratum and R. delavayi, respectively.